Information recording method, information recording apparatus, program and computer readable information storage medium

ABSTRACT

In a method for writing data to an information recording medium having a plurality of recording layers, user data is written across between a plurality of the recording layers, and data other than the user data is written in a predetermined zone of the recording layer. Thereby, since the user data is written continuously upon switching of a recording layer without data other than the user data being written, it is possible to avoid interruption of writing of the user data to the recording layers.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a U.S. continuation application filed under 35 USC111(a) claiming benefit under 35 USC 120 and 365(c) of PCT applicationJP2004/003083, filed on Mar. 10, 2004, which claims priority ofApplications Ser. Nos. 2003-083930 and 2004-013260, filed in Japan onMar. 25, 2003 and Jan. 21, 2004, respectively. The foregoingapplications are hereby incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an information recording method, aninformation recording apparatus, a program and a computer readableinformation storage medium for writing data to an information recordingmedium having a plurality of recording layers.

2. Description of the Related Art

Recently, along with improvement of the performance in a personalcomputer (PC), the personal computer becomes to be able to handle AV(Audio-Visual) information such as music, pictures or such. Since suchAV information has a very large information size, an optical disk suchas a DVD (Digital Versatile Disc) has taken attention as an informationrecording medium, and, along with price reduction thereof, an opticaldisk apparatus as an information recording/reproduction apparatuses havespread as peripheral devices for PCs.

As a DVD-ROM, there exist DVDs having single recording layers and DVDseach having two recording layers. However, as writeable recording-typeDVDs, only DVD having single recording layers, such as DVD+R(Recordable), DVD-RW (Rewriteable), DVD-RAM (Random Access Memory) orsuch exist. Therefore, a recording-type double-layer DVD having tworecording layers has been studied recently. This medium has aconfiguration such that, as a result of data being written thereto inthe same manner as that in the DVD-ROM, it has a recording capacity sameas that of the DVD-ROM, and also, it has a compatibility with theDVD-ROM.

A reproduction-only-type double-layer DVD has two types of tracksystems, i.e., a parallel track path system (PTP system) in which atrack on a second layer has a direction from the central side to theperipheral side same as that in a track of a first layer, and anopposite track path system (OTP system) in which a track on a secondlayer has a direction from the peripheral side to the central side.

FIG. 12 generally shows a logical format of a recording-typedouble-layer DVD in the PTP system while FIG. 13 generally shows alogical format of a recording-type double-layer DVD in the OTP system.In FIGS. 12 and 13, the left hand corresponds to the central side of theoptical disk while the right hand corresponds to the peripheral side ofthe optical disk.

As shown in FIG. 12, in each layer of a first recording layer and asecond recording layer, from the central side of the optical disk, alead-in zone (LEAD-IN ZONE), a data zone (DATA ZONE) and a lead-out zone(LEAD-OUT ZONE) are provided. In other words, in each layer of the firstand second recording layers, data is written from the central sidetoward the peripheral side of the optical disk. It is noted that, in thePTP system, a radial position of an address at which the data zonestarts is equal between the first and second layer. For example, each ofboth starts at a physical address of 30000H.

As shown in FIG. 13, in a first recording layer, from the central sideof the optical disk, a lead-in zone (LEAD-IN ZONE), a data zone (DATAZONE) and a middle zone (MIDDLE ZONE) are provided. In a secondrecording layer, from the peripheral side of the optical disk, a middlezone (MIDDLE ZONE), a data zone (DATA ZONE) and a lead-out zone(LEAD-OUT ZONE) are provided. In other words, in the first recordinglayer, data is written from the central side toward the peripheral sideof the optical disk, while, in the second recording layer, data iswritten from the peripheral side toward the central side of the opticaldisk. It is noted that, in the OTP system, a radial position of anaddress at which the data zone starts in the second recording layer isequal to a radial position of an address at which the data zone ends inthe first recording layer. Further, a physical address at which the datazone starts in the second recording layer is an address bit-invertedfrom an address at which the data zone ends in the first recordinglayer.

Thus, in the logical format in the recording-type double-layer DVD, thedata other than the user data (for example, the lead-in (LEAD-IN) data,lead-out (LEAD-OUT) data, middle (MIDDLE) data or such) is writtenbefore or after the user data.

On the other hand, a technology of previously creating data to bewritten to a multilayer optical disk having a plurality of recordinglayers has been proposed. According to the technology, data to bewritten to a multilayer optical disk is previously created, and, uponswitching of a recording layer, data other than user data (for example,lead-out data) is written (see Japanese Laid-open Patent Application No.2000-48542).

SUMMARY OF THE INVENTION

However, in a recording-type multilayer optical disk, logically, aplurality of layers are treated as a single layer in a writing process.However, when data other than user data, for example, when dataindicating layer switching or such is written during writing of the userdata, the processing of writing of the user data to a recording layer isinterrupted. In particular, in a case of a video recording occasion inwhich user data should be continuously written, interruption of thewriting processing during the processing of writing of the user data fora long interval is problematic.

An object of the present invention is to avoid interruption ofprocessing of writing user data to a recording layer.

Another object of the present invention is to enable reading of userdata already written to a recording layer, at predetermined timing.

An information recording method according to the present invention forwriting data into an information recording medium having a plurality ofrecording layers, includes a step of writing the data across between aplurality of the recording layers (continuously), and a step of, afterwriting the user data, writing data other than the user data to apredetermined zone of the recording layer.

According to the present invention, user data is writing across betweenthe plurality of recording layers (continuously), and, after thecompletion of writing of the user data, the data indicating switching ofthe recording layer is written at a zone around the boundary of therecording layer. In other words, even at a portion at which therecording layer is switched, the data indicating switching of therecording layer is not written but the user data is written continuouslywithout interruption. Accordingly, during this time, no interruptionoccurs in the processing of writing of the user data to the recordinglayer.

According to an information recording method in another aspect of thepresent invention, the information recording method for writing data toan information recording medium having a plurality of recording layersincludes a step of writing data across between a plurality of recordinglayers skipping a zone around the boundary of the plurality of recordinglayers, and a step of, after writing the user data, writing dataindicating switching the layer at the zone around the boundary.

According to the present invention, the user data is writing acrossbetween the plurality of recording layers (continuously), and, after thecompletion of writing of the user data, the data indicating switching ofthe recording layer is written at the zone around the boundary of therecording layer. In other words, even at a portion at which therecording layer is switched, the data indicating switching of therecording layer is not written but the user data is written continuouslywithout interruption. Accordingly, during this time, no interruptionoccurs in the processing of writing of the user data to the recordinglayer.

Further, in the above-mentioned information recording methods, it ispreferable that, the information recording medium is an informationrecording medium in which recording is carried out in the parallel trackpath (PTP) system; the zone around the boundary includes a lead-out zone(LEAD-OUT ZONE) in a first recording layer in which the user data hasbeen written, and a lead-in zone (LEAD-IN ZONE) of a second recordinglayer in which the user data has been written across from the firstrecording layer; and the data indicating switching of the layer islead-out (LEAD-OUT) data written in the lead-out zone of the firstrecording layer and lead-in (LEAD-IN) data written in the lead-in zoneof the second recording layer.

Thus, after writing of the user data to the information recording mediumin the PTP system, the lead-out data is written in the lead-out zone ofthe first recording layer, and then, the lead-in data is written in thelead-in zone of the second recording layer. As a result, in theinformation recording medium in the PTP system, upon switching of therecording layer, the data indicating switching of the recording layer isnot written but the user data is written continuously (across betweenthe two layers). Thereby, it becomes possible to avoid interruption ofthe processing of writing of the user data to the recording layer.

Alternatively, in the above-mentioned information recording methods, itis preferable that, the information recording medium is an informationrecording medium in which recording is carried out in the opposite trackpath (OTP) system; the zone around the boundary includes a middle zone(MIDDLE ZONE) in a first recording layer in which the user data has beenwritten and a middle zone (MIDDLE ZONE) of a second recording layer inwhich the user data has been written across from the first recordinglayer; and the data indicating switching of the layer is middle (MIDDLE)data written in the middle zone of the first recording layer and middle(MIDDLE) data written in the middle zone of the second recording layer.

Thus, after writing of the user data to the information recording mediumin the OTP system, the middle data is written in the middle zones in thefirst and second recording layers. As a result, in the informationrecording medium in the OTP system, upon switching of the recordinglayer, the data indicating switching of the recording layer is notwritten but the user data is written continuously (across between thetwo layers). Thereby, it becomes possible to avoid interruption of theprocessing of writing of the user data to the recording layer.

Further, in the information recording methods described above, in thestep of writing the user data, it is preferable to write dummy dataimmediately before the data zone (DATA ZONE) of a recording layer towhich writing is made subsequently, after writing the user data to thepredetermined recording layer.

By thus writing the dummy data immediately before the data zone (DATAZONE) of the recording layer to which recording is performedsubsequently, after writing the user data in the predetermined recordinglayer, it becomes possible to read the user data written in thesubsequent recording layer at predetermined timing even in a case wherethe lead-in (LEAD-IN) data in the PTP system or the middle (MIDDLE) datain the OTP system has not been written, for example, even in a case ofso-called follow-up reproduction to reproduce the user data duringwriting of the user data, for example.

Furthermore, in the information recording methods, in the step ofwriting the user data, after writing the user data in the predeterminedrecording layer, it is preferable to write dummy data at a top of thedata zone (DATA ZONE) of the recording layer to which writing is carriedout subsequently.

By thus writing the dummy data at the top of the data zone (DATA ZONE)of the recording layer to which recording is performed subsequentlyafter writing the user data in the predetermined recording layer, itbecomes possible to read the user data written in the subsequentrecording layer at predetermined timing even in a case where the lead-in(LEAD-IN) data in the PTP system or the middle (MIDDLE) data in the OTPsystem has not been written, for example, even in a case of so-calledfollow-up reproduction to reproduce the user data during writing of theuser data, for example.

Further, in the information recording methods described above, in thestep of writing the user data, it is preferable to write dummy dataimmediately before the data zone (DATA ZONE) of a recording layer towhich writing is made subsequently, before writing the user data to theplurality of recording layers.

Since the dummy data is thus written before the user data is written tothe recording layers, no time is required to write the dummy data at aportion of switching of the recording layer during writing of the userdata. Accordingly, it is possible to positively avoid interruption ofprocessing of writing of the user data to the recording layers.

Further, in the information recording methods described above, in thestep of writing the user data, it is preferable to write dummy data at atop of the data zone (DATA ZONE) of a recording layer to which writingis made subsequently, before writing the user data to the plurality ofrecording layers.

Since the dummy data is thus written before the user data is written tothe recording layers, no time is required to write the dummy data at aportion of switching of a recording layer during writing of the userdata. Accordingly, it is possible to positively avoid interruption ofthe processing of writing of the user data to the recording layers.

Furthermore, it is possible to realize the present invention in a formof an information recording apparatus, an information recording program,or a computer readable information storage medium. Also in such a case,the above-mentioned information recording method should be carried outconsequently, and thus, the same advantages can be obtained.

Thus, according to the present invention, an information recordingmethod for writing data to an information recording medium having aplurality of recording layers includes a step of (continuously) writinguser data across between a plurality of the recording layers and a stepof, after writing the user data, writing data other than the user datain a predetermined zone of the recording layer. Thereby, since the dataother than the user data is written in the predetermined zone in therecording layer after the user data is written across between theplurality of recording layers, the user data is continuously writtenwithout the data other than the user data being written upon switchingof the recording layer. Accordingly, it is possible to avoidinterruption of the processing of writing of the user data to therecording layers.

Further, an information recording method for writing data to aninformation recording medium having a plurality of recording layersincludes a step of (continuously) writing user data across between aplurality of the recording layers skipping a zone around the boundary ofthe plurality of the recording layers and a step of, after writing theuser data, writing data indicating switching the recording layer in thezone around the boundary. Thereby, since the data indicating switchingof the recording layer is written in the zone around the boundary of therecording layers after the user data is written across between theplurality of recording layers, the user data is continuously writtenwithout the data other than the user data being written upon switchingof the recording layer. Accordingly, it is possible to avoidinterruption of processing of writing of the user data to the recordinglayers.

Further, a case is assumed where the information recording medium is aninformation recording medium such as that to which recording isperformed in the parallel track path (PTP) system, the zone around theboundary includes the lead-out zone (LEAD-OUT ZONE) of the firstrecording layer in which the user data is written and the lead-in zone(LEAD-IN ZONE) of the second recording layer in which the user data iswritten across from the first recording layer, and the data indicatingswitching of the recording layer includes the lead-out (LEAD-OUT) datawritten in the lead-out zone of the first recording layer and thelead-in (LEAD-IN) data written in the lead-in zone of the secondrecording layer. In this case, after the user data is written in theinformation recording medium according to the PTP system, the lead-outdata is written in the lead-out zone of the first recording layer, andthe lead-in data is written in the lead-in zone of the second recordinglayer. Thereby, the user data is continuously (across between the tworecording layers) written in the information recording medium accordingto the PTP system without the data indicating switching of the recordinglayer being written upon switching of the recording layer. As a result,it becomes possible to avoid interruption of the processing of writingthe user data to the recording layers.

Further, another case is assumed where the information recording mediumis an information recording medium such as that to which recording isperformed in the opposite track path (OTP) system, the zone around theboundary includes the middle zone (MIDDLE ZONE) of the first recordinglayer in which the user data is written and the middle zone (MIDDLEZONE) of the second recording layer in which the user data is writtenacross from the first recording layer, and the data indicating switchingof the recording layer includes the middle (MIDDLE) data written in themiddle zone of the first recording layer and the middle (MIDDLE) datawritten in the middle zone of the second recording layer. In this case,after the user data is written in the information recording mediumaccording to the OTP system, the middle data is written in the middlezone of the first recording layer, and the middle data is written in themiddle zone of the second recording layer. Thereby, the user data iscontinuously (across between the two recording layers) written in theinformation recording medium according to the OTP system without thedata indicating switching of the recording layer being written uponswitching of the recording layer. As a result, it becomes possible toavoid interruption of processing of writing the user data to therecording layers.

Further, by writing dummy data immediately before the user data (USERDATA) of a recording layer to which writing is carried out subsequentlyafter writing the user data in the predetermined recording layer in theabove-mentioned step of writing the user data, it becomes possible toread the user data written in the subsequent recording layer atpredetermined timing even in a case where the lead-in (LEAD-IN) data inthe PTP system or the middle (MIDDLE) data in the OTP system has notbeen written, for example, even in a case of so-called follow-upreproduction to reproduce user data during writing of the user data, forexample.

Further, by writing dummy data at a top of the user data (USER DATA) ofa recording layer to which writing is carried out subsequently afterwriting the user data in the predetermined recording layer in theabove-mentioned step of writing the user data, it becomes possible toread the user data written in the subsequent recording layer atpredetermined timing even in a case where the lead-in (LEAD-IN) data inthe PTP system or the middle (MIDDLE) data in the OTP system has notbeen written, for example, even in a case of so-called follow-upreproduction to reproduce user data during writing of the user data, forexample.

Further, by writing dummy data immediately before the user data (USERDATA) of a recording layer to which writing is carried out subsequentlybefore writing the user data in the plurality of recording layers in theabove-mentioned step of writing the user data, no time is required towrite the dummy data upon switching of a recording layer. Accordingly,it is possible to positively avoid interruption of processing of writingof the user data to the recording layers.

Further, by writing dummy data at a top of the user data (USER DATA) ofa recording layer to which writing is carried out subsequently beforewriting the user data in the plurality of recording layers in theabove-mentioned step of writing the user data, no time is required towrite the dummy data upon switching of a recording layer. Accordingly,it is possible to positively avoid interruption of processing of writingof the user data to the recording layers.

Further, by configuring the dummy data to have a minimum necessary datasize required for indicating the top of data or such, it is possible tocontrol interruption required to write the dummy data to be a very smallone. As a result, it becomes possible to carry out writing of the userdata substantially without interruption.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a block diagram showing a general configuration of anoptical disk apparatus as an information recording apparatus accordingto a first embodiment of the present invention.

FIG. 2 shows a block diagram showing a general configuration of a PCconnected to the optical disk apparatus.

FIG. 3 shows a flow chart showing a flow of processing of writingaccording to the PTP system according to the first embodiment of thepresent invention.

FIG. 4 shows a flow chart showing a flow of processing of writingaccording to the OTP system according to the first embodiment of thepresent invention.

FIG. 5 shows a flow chart showing a flow of processing of writingaccording to a second embodiment of the present invention.

FIG. 6 roughly shows a position at which dummy data is written in thePTP system according to the second embodiment of the present invention.

FIG. 7 roughly shows a position at which dummy data is written in theOTP system according to the second embodiment of the present invention.

FIG. 8 shows a flow chart showing a flow of processing of writingaccording to a variant embodiment 1 of the second embodiment of thepresent invention.

FIG. 9 roughly shows a position at which dummy data is written in thePTP system according to the variant embodiment 1 of the presentinvention.

FIG. 10 roughly shows a position at which dummy data is written in theOTP system according to the variant embodiment 1 of the presentinvention.

FIG. 11 shows a flow chart showing a flow of processing of writingaccording to a variant embodiment 2 of the second embodiment of thepresent invention.

FIG. 12 roughly shows a logical format in a recording-type double-layerDVD according to the PTP system.

FIG. 13 roughly shows a logical format in a recording-type double-layerDVD according to the OTP system.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

A first embodiment of the present invention is described with referenceto FIGS. 1 through 4. FIG. 1 is a block diagram showing a generalconfiguration of an optical disk apparatus 1 as an information recordingapparatus.

The optical disk apparatus 1 includes a spindle motor 3 rotating anddriving an optical disk 2 as an information recording medium, an opticalpickup device 4, a laser control circuit 5, a motor driver 6, areproduction signal processing circuit 7, a servo controller 8, a bufferRAM 9, a buffer manager 10, an interface 11, a ROM 12, a CPU 13 and aRAM 14. Arrows shown in FIG. 1 show typical flows of signals orinformation, and do not show all the connection relationship between therespective blocks.

As the optical disk 2, a DVD as a recording-type multilayer optical diskis applied. Specifically, the optical disk 2 is one having two recordinglayers.

The optical pickup device 4 includes a semiconductor laser as a lightsource, an optical system including an objective lens which leads laserlight emitted from the semiconductor laser to a recording surface of theoptical disk 2, and also, leads reflected light from the optical disk 2to a predetermined light receiving position, a light receiving devicedisposed at the light receiving position and receiving the returnedlight and a driving system (focusing actuator, a tracking actuator, aseek motor and so forth) (not shown). From the light receiving device,an electronic current (electronic current signal) according to a lightreception amount is output to the reproduction signal processing circuit7.

The servo controller 8 generates a control signal controlling thefocusing actuator in the optical pickup device 4 based on a focus errorsignal, and generates a control signal controlling the tracking actuatorin the optical pickup device 4 based on a tracking error signal. Thesecontrol signals are output to the motor driver 6 from the servocontroller 8.

The motor driver 6 drives the focusing actuator and the trackingactuator in the optical pickup device 4 based on the control signalsfrom the servo controller 8. The motor driver 6 controls the spindlemotor 3 so that a line velocity of the optical disk 2 may be constantbased on instructions from the CPU 13. Further, the motor driver 6drives the seek motor in the optical pickup device 4 and moves theoptical pickup device 4 toward a target track on the optical disk 2 in aradial direction based on instructions from the CPU 13.

The interface 11 acts as a bi-directional communication interface with ahost (for example, a PC 101 as an information processing apparatus shownin FIG. 2) as an external apparatus, and is configured to conform to astandard interface such as an ATAPI, an SCSI or such

The CPU 11 configures a microcomputer together with the ROM 12 and RAM14 provided in the optical disk apparatus 1. In the ROM 12 which alsoacts as a storage medium, a program which includes a control programdescribed later described in a code recognizable by the CPU 13 isstored. The CPU 13 controls operation of the respective parts describedabove, according to the program stored in the ROM 12, and also,temporarily stores data necessary for the control in the RAM 14. Whenpower is turned on in the optical disk apparatus 1, the program storedin the ROM 12 is loaded (installed) in a main memory (not shown) of theCPU 13.

The PC 101 as an information processing apparatus is described next. ThePC 101 is an abbreviation of a personal computer. FIG. 2 is a blockdiagram showing a general configuration of the PC 101 connected with theoptical disk apparatus 1.

The PC 101 has a configuration such that respective parts are connectedwith a CPU 104 which configures a microcomputer together with a ROM 102and a RAM 103 via a bus line 105. In the ROM 102, fixed data is fixedlyrecorded, while, in the RAM 103, variable data is recorded in a mannerof being able to be changed. To the microcomputer, storage devices suchas an HDD (hard disk drive), an FDD (flexible disk drive) and a CD-ROMdrive 108 are connected via the bus line 105. In the HDD 106, an OS(operating system), various sorts of application programs and so forthare stored, part thereof is copied to the RAM 103 at a time of startingup, and is used by the CPU 104 to control the respective parts.

To the CPU 104, further a display 109, an input device 110 such as akeyboard, mouse and so forth, and an interface 111 are connected via thebus line 105. By means of the interface 111, connection with an externalapparatus is made possible. For example, the above-described opticaldisk apparatus 1 is connected with the PC 101 via the interface 111.

Writing processing carried out by the CPU 13 based on the program storedin the ROM 12 is described with reference to FIGS. 3, 4, 12 and 13. Userdata written to the optical disk 2 in the writing processing includes,for example, video data including voice data, picture data and so forth(the same for the other embodiments).

FIG. 3 is a flow chart showing a flow of the writing processingaccording to the PTP system in the embodiment of the present invention.A method of writing data to the optical disk 2 in the writing processingaccording to the PTP system is described (see FIG. 12). As shown in FIG.3, the CPU 13 first carries out processing of writing user data to afirst recording layer (in Step S1). The user data is written in a datazone (DATA ZONE) in the first recording layer. After that, continuous tothe processing of writing of the user data to the first recording layer,processing of writing of user data to a second recording layer iscarried out (S2). The user data is written in a data zone (DATA ZONE) ofthe second recording layer continuous to the user data written to thedata zone (DATA ZONE) of the first recording layer. In other words, theuser data is written across between the first recording layer and thesecond recording layer. Then, after the writing of the user data to thesecond recording layer is completed, lead-out (LEAD-OUT) data is writtento the first recording layer, and lead-in (LEAD-IN) data is written tothe second recording layer (S3). The lead-out (LEAD-OUT) data is writtenin a lead-out zone (LEAD-OUT ZONE) in the first recording layer whilethe lead-in (LEAD-IN) data is written in a lead-in (LEAD-IN) zone in thesecond recording layer. After that, or simultaneously, the lead-in(LEAD-IN) data is written in a lead-in zone (LEAD-IN ZONE) in the firstrecording layer, while the lead-out (LEAD-OUT) data is written in alead-out zone (LEAD-OUT ZONE) in the second recording layer. Thelead-out zone in the first recording layer and the lead-in zone in thesecond recording layer act as around boundary zones, and the lead-outdata and lead-in data acts as data indicating switching of the recordinglayers.

It is assumed that, before the above-mentioned writing processing iscarried out, address information is built in the optical disk 2 inwell-known wobble processing, and, further, an address range of the datazone is recorded for each recording layer in the lead-in zone.Therefore, the optical disk apparatus 1 which carries out the writingprocessing first reads out this information and thus recognizes theposition of the data zone. Thereby, when the user data is written to theoptical disk 2 continuously in Steps S1 and S2, the writing is carriedout skipping the lead-in zone and the lead-out zone other than the datazone. This assumption is also applied to any other embodiments andvariant embodiments of the present invention described later. In a caseof writing processing according to the OTP system, writing is carriedout skipping the lead-in zone, the lead-out zone and the middle zoneother than the data zone.

FIG. 4 is a flow chart showing a flow of writing processing according tothe OTP system in the embodiment of the present invention. Aninformation recording method for writing data to the optical disk 2 inwriting processing according to the OTP system is described (see FIG.13). As shown in FIG. 4, the CPU 13 first carries out writing of userdata to the first recording layer (in Step S11). The user data iswritten in a data zone (DATA ZONE) of the first recording layer. Afterthat, continuously to the user data written to the first recordinglayer, user data is written to the second recording layer (S12). Theuser data is written to a data zone (DATA ZONE) of the second recordinglayer continuous to the user data written to the data zone (DATA ZONE)of the first recording layer. In other words, the user data is writtenacross between the first recording layer and the second recording layer.After the writing of the user data to the second recording layer, middle(MIDDLE) data is written to the first recording layer, and middle(MIDDLE) data is written to the second recording layer (S13). The middle(MIDDLE) data is written to a middle zone (MIDDLE ZONE) of the firstrecording layer and to a middle zone (MIDDLE ZONE) of the secondrecording layer. After that, or simultaneously, the lead-in (LEAD-IN)data is written in a lead-in zone (LEAD-IN ZONE) of the first recordinglayer and the lead-out (LEAD-OUT) data is written in a lead-out zone(LEAD-OUT ZONE) of the second recording layer. The middle zone in thefirst recording layer and the middle zone in the second recording layeract as around boundary zones, and the middle data acts as dataindicating switching of the recording layers.

Thus, according to the embodiment of the present invention, after theuser data is written continuously to the data zones (DATA ZONES) of thefirst and second recording layers (across between the two recordinglayers), the data other than the user data (for example, the lead-in(LEAD-IN) data, the lead-out (LEAD-OUT) data, the middle (MIDDLE) dataor such) is written. Thereby, the data other than the user data is notwritten upon switching from the first recording layer to the secondrecording layer but the user data is continuously written. As a result,it is possible to avoid interruption of the processing of writing of theuser data to the recording layers.

The above-described control processing is carried out by the CPU 13 ofthe optical disk apparatus 1 according to the computer program recordedin the ROM 12 of the optical disk apparatus 1 as firmware, for example.In this case, the ROM 12 acts as storage medium storing therein thecomputer program.

Without limiting to the above-mentioned example, a configuration may bemade such that, for example, according to the computer program copied tothe RAM 103 at a time of starting up from the HDD 106, the CPU 104 inthe PC 101 transmits operation instructions to the optical diskapparatus 1, and thereby, the same processing is carried out (the samefor the other embodiments). In this case, the computer program copied tothe RAM 103 of the PC 101 may be one stored in the HDD 106 in a form ofan application program, or may be one incorporated in the OS. In a casewhere the application program is stored in the HDD 106, the applicationprogram is distributed in such a manner that it is recorded in arecording medium such as a CD-ROM or such. Then, the computer program isread out by means of the FDD 107 or the CD-ROM drive 108 in the PC 101,and then, is stored in the HDD 106. Therefore, in the example mentionedabove, the HDD 106, the RAM 103, the FD, the CD-ROM or such acts as astorage medium storing therein the computer program.

In the two examples described above, the optical disk apparatus 1 or thePC 101 acts as a computer carrying out the processing according to theflow chart shown in FIG. 3 or FIG. 4 unique to the embodiment. However,it is not necessary to limit thereto, but a configuration may beprovided such that such processing is carried out according to thecomputer program which is distributed to both the optical disk apparatus1 and the PC 101. In any method, in a case where all or part of thecontrol processing is carried out by the PC 101, the computer program isinstalled in the PC 101 whereby the optical disk apparatus 1 can carryout processing such as that shown in FIG. 3 or FIG. 4.

A second embodiment of the present invention is described with referenceto FIGS. 5 through 11. The same reference numerals are given to partssame as those in the first embodiment, and description thereof isomitted.

A basic configuration of the present embodiment is approximately same asthat in the first embodiment. Difference between the present embodimentand the first embodiment is a flow of writing processing. An informationrecording method for writing data to the optical disk 2 is describedhere.

FIG. 5 is a flow chart showing a flow of writing processing according tothe present embodiment, FIG. 6 roughly illustrates a position to writedummy data according to the PTP system in the present embodiment, andFIG. 7 roughly illustrates a position to write dummy data according tothe OTP system in the present embodiment. In FIGS. 6 and 7, the lefthand corresponds to the central side in the optical disk 2 while theright hand corresponds to the peripheral side in the optical disk 2.

As shown in FIG. 5, first, the CPU 13 carries out processing of writinguser data to a first recording layer (in Step S21). After that,immediately before a data zone (DATA ZONE) in a second recording layer,a predetermined size of dummy data (corresponding to half-tone-dotfilled parts in FIGS. 6 and 7) is written (S22). For example, as shownin FIGS. 6 and 7, the predetermined size of dummy data is writtenimmediately before the data zone (DATA ZONE). After the predeterminedsize of dummy data is written, processing of writing user data to thesecond recording layer is carried out (S23). The user data is writtenacross between the first and second recording layers. Then, afterwriting of the user data to the second recording layer is completed, theCPU 13 carries out Step S3 in the PTP system or carries out Step S13 inFIG. 4 in the OTP system.

FIG. 8 is a flow chart showing a flow of writing processing in a variantembodiment 1 of the present embodiment, and FIG. 9 roughly shows aposition to write dummy data according to the PTP system in the variantembodiment 1, and FIG. 10 roughly shows a position to write dummy dataaccording to the OTP system in the variant embodiment 1. In FIGS. 9 and10, the left hand corresponds to the central side in the optical disk 2while the right hand corresponds to the peripheral side in the opticaldisk 2.

As shown in FIG. 8, first, the CPU 13 carries out processing of writinguser data to a first recording layer (in Step S31). After that, at a topof a data zone (DATA ZONE) in a second recording layer, a predeterminedsize of dummy data (corresponding to half-tone-dot filled parts in FIGS.9 and 10) is written (S32). For example, as shown in FIGS. 9 and 10, thepredetermined size of dummy data is written at the top of the data zone(DATA ZONE). After the predetermined size of dummy data is written,processing of writing user data to the second recording layer is carriedout (S33). In detail, after the predetermined size of dummy is written,a position to start writing of the user data is shifted for the dummydata, and then, the user data is written. The user data is writtenacross between the first and second recording layers. Then, afterwriting of the user data to the second recording layer is completed, theCPU 13 carries out Step S3 in the PTP system or carries out Step S13 inFIG. 4 in the OTP system.

Thus, according to the present embodiment and the variant embodiment 1of the present invention, after the user data is written in the firstrecording layer, the dummy data is written immediately before or at thetop of the user data to write on the second recording layer. Thereby,even when the lead-in (LEAD-IN) data in the PTP system or the middle(MIDDLE) data in the OTP system is not yet written, for example, even ina case of carrying out follow-up reproduction of reproducing the userdata while writing the same, it is possible to detect the top of theuser data written in the second recording layer by reading the dummydata, whereby it is possible to read out the user data written in thesecond recording layer at predetermined timing.

FIG. 11 is a flow chart showing a flow of writing processing accordingto a variant embodiment 2 of the present embodiment. As shown in FIG.11, first, the CPU 13 writes a predetermined size of dummy data (seeFIGS. 6, 7, 9 and 10) immediately before a data zone (DATA ZONE) of asecond recording layer, or at a top of the data zone (DATA ZONE) of thesecond recording layer (S41). After that, the CPU 13 carries outprocessing of writing user data to the first recording layer (S42), andcarries out processing of writing user data to the second recordinglayer (S43). Then, after writing of the user data to the secondrecording layer is completed, the CPU 13 carries out Step S3 in the PTPsystem or carries out Step S13 in FIG. 4 in the OTP system.

Thus, according to the variant embodiment 2 of the present embodiment,by previously writing the dummy data before writing the user data to therecording layers, a time to write the dummy data is not necessary uponswitching of the recording layers. Thereby, it is possible to positivelyavoid interruption of the processing of writing of the user data to therecording layers.

Embodiments of the present invention are not limited to those mentionedabove and, other various embodiments are contrivable within the scopeclaimed in the claims below.

Further, the present application is based on Japanese Priority PatentApplications Nos. 2003-083930 and 2004-013260, filed on Mar. 25, 2003and Jan. 21, 2004, respectively, and also, International (PCT) PatentApplication No. JP2004/003083, the contents of which are therebyincorporated by reference.

1-28. (canceled)
 29. A method for writing data to an information recording medium having a plurality of recording layers, the layers having at least a first layer and a second layer, the information recording medium to which recording is made being configured according to an opposite track path system, the method comprising the steps of: writing user data in a data zone on the first layer; subsequently, writing a pre-determined amount of data other than user data immediately before a data zone in the second layer; subsequently, writing user data in said data zone on the second layer; and skipping a middle zone for the first layer after the step of writing user data in a data zone on the first layer but before the step of writing a pre-determined amount of data other than user data immediately before a data zone in the second layer.
 30. A method for writing data to an information recording medium having a plurality of recording layers, the layers having at least a first layer and a second layer, the information recording medium to which recording is made being configured according to an opposite track path system, the method comprising the steps of: writing user data in a data zone on the first layer; writing a pre-determined amount of data other than user data immediately before a data zone in the second layer, wherein the pre-determined amount is an amount smaller than a size of a middle zone for the second layer; and writing user data in said data zone on the second layer.
 31. The method of claim 30 wherein the step of writing a pre-determined amount of data other than user data comprises writing a pre-determined amount of dummy data.
 32. The method of claim 31, wherein the step of writing a pre-determined amount of dummy data is performed in the middle zone for the second layer.
 33. The method of claim 32, wherein the step of writing a pre-determined amount of dummy data in the middle zone for the second layer is done immediately before the step of writing user data in said data zone on the second layer.
 34. A method for writing data to an information recording medium having a plurality of recording layers, the layers having at least a first layer and a second layer, the information recording medium to which recording is made being configured according to an opposite track path system, the method comprising the steps of: writing user data in a data zone on the first layer; skipping a middle zone of the first layer; writing a pre-determined amount of data other than user data immediately before a data zone in the second layer; and writing user data in said data zone on the second layer.
 35. An information recording apparatus for writing data to an information recording medium having at least first and second recording layers and being configured as an opposite track path system, the apparatus comprising: a first writing part writing user data in respective first and second data zones on the first and second recording layers and writing a pre-determined amount of data other than user data immediately before the data zone on the second recording layer, wherein the pre-determined amount of data is an amount smaller than the size of a middle zone for the second recording layer.
 36. The information recording apparatus as claimed in claim 35, further comprising: a second writing part writing data which indicates a switching of the layers in a zone around a boundary of either said first or said second recording layer.
 37. An information recording apparatus for writing data to an information recording medium having at least first and second recording layers and being configured as an opposite track path system, the apparatus comprising: a first writing part writing user data in respective first and second data zones on the first and second recording layers and writing a pre-determined amount of data other than user data immediately before the data zone on the second recording layer, wherein the first writing part is configured to skip a middle zone area of the first recording layer before writing said pre-determined amount of data other than user data is said second recording layer.
 38. The information recording apparatus as claimed in claim 37, further comprising: a second writing part writing data which indicates a switching of the layers in a zone around a boundary of either said first or said second recording layer.
 39. A program, installed in a computer provided in an information recording apparatus for writing data to an information recording medium having at least first and second recording layers, the information medium to which recording is made being configured according to an opposite track path system, the program comprising instructions for causing the computer to carry out: a step of writing user data in a data zone on the first layer; a step of writing a pre-determined amount of data other than user data immediately before a data zone in the second layer, wherein the amount of data is smaller than a size of a middle zone area for the second layer; and a step of writing user data in said data zone on the second layer.
 40. The program as claimed in claim 39, wherein: the step of writing the data other than user data immediately before a data zone in the second layer occurs just after the step of writing user data in the data zone of the first layer and just prior to the step of writing user data in the data zone on the second layer.
 41. The program as claimed in claim 39, wherein the step of writing a pre-determined amount of data other than user data comprises writing a pre-determined amount of dummy data.
 42. A program, installed in a computer provided in an information recording apparatus for writing data to an information recording medium having at least first and second recording layers, the information medium to which recording is made being configured according to an opposite track path system, the program comprising instructions for causing the computer to carry out: a step of writing user data in a data zone on the first layer; a step of skipping a middle zone of the first layer; a step of writing a pre-determined amount of data other than user data immediately before a data zone in the second layer; and a step of writing user data in said data zone on the second layer.
 43. The program as claimed in claim 42, wherein the pre-determined amount of data other than user data is an amount smaller than a size of a middle zone for the second layer.
 44. The program as claimed in claim 42, wherein the step of writing a pre-determined amount of data other than user data comprises writing a pre-determined amount of dummy data. 